In a wide variety of space missions, there is a need for a space craft in the nature of a spaceplane which can take off from land or a space station at any orbital inclination on short notice, for example one hour or less, without the need for dropping boosters toward Earth. Such a spaceplane must also enter into low-Earth orbit and land anywhere within a preselected zone from high-inclination orbits.
A major difficulty in designing such a craft is the requirement for wing structures needed during reentry into the atmosphere in order to obtain stability and steering control. Of course, such structures are disadvantageous for space travel outside the atmosphere due to unnecessary extra weight they add.
In military applications where a manned space craft is employed, radar radomes are often required to be mounted on the craft exterior. This presents major engineering problems inasmuch as the material must withstand extremely high temperatures during reentry.
U.S. Pat. No. 3,534,924, issued Oct. 20, 1970, to Spencer, Jr., et al., discloses a variable geometry manned orbital vehicle in which auxiliary pivotal wings are incorporated to allow retention of an aerodynamically efficient lifting body shape at hypersonic speeds with the auxiliary wings folded into a stored position. At lower speeds the auxiliary wings are deployed at sweep angles which vary as required to provide improvements in lift, lift-drag ratio, and in the stability characteristics of the vehicle.
Although this craft represents an advance over its prior art, it does not provide a solution to the problems of high heat environment for a radar radome. Further, the structure of the Spencer, Jr., et al., patent does not locate the mean aerodynamic center of the auxiliary wing at the same longitudinal location as the center of gravity of the craft. This detracts from the optimum stability characteristics.